This application is based upon, claims the benefit of priority of, and incorporates by reference the contents of prior Japanese Patent Application No. 2001-283609 filed Sep. 18, 2001.
1. Field of the Invention
The present invention relates to a vehicle air conditioning system to be mounted on a vehicle. More specifically, the air conditioning system is provided with a sealing member for sealing a clearance between an air conditioning case and a heat exchanger.
2. Description of the Related Art
Generally, a sealing member is attached to the periphery of a heat exchanger installed inside an air conditioning case, so that any clearance between the heat exchanger and the air conditioning case is sealed to prevent air leakage. As shown in a related art arrangement of FIG. 7, a plate (32) with lip (38), which undergoes elastic deformation when pressed against the air conditioning case, is formed integrally with a sealing member (30).
In the situation where a heat exchanger (20) in installed inside the air conditioning case by inserting the heat exchanger (20) in the longitudinal direction (a direction indicated by an arrow E of FIG. 7) of the lip (38), the lip (38) rubs against the air conditioning case during insertion and receives a shear force Ps. Consequently, deformation in the longitudinal direction E occurs at the end portion of the lip (38). This deformation readily results in a clearance between the lip (38) and the air conditioning case, which further results in deterioration of the sealing ability of the sealing member (30) between the lip (38) and the air conditioning case.
The present invention is devised in view of the foregoing, and therefore, has an object to enhance the sealing ability of a sealing member for sealing a clearance between an air conditioning case and a heat exchanger.
In order to achieve the above and other objects, a first aspect of the present invention provides a vehicle air conditioning system having an air conditioning case defining an air channel, a heat exchanger to be installed inside the air conditioning case for exchanging heat with air passing through the air channel, and a sealing member attached to a periphery of the heat exchanger for sealing a clearance between the heat exchanger and the air conditioning case. The sealing member is provided with, as an integral part thereof, plates of main lips and sub-lips that undergo elastic deformation when pressed against the air conditioning case. The sub-lips are formed to branch from surfaces of the plates forming their respective main lips.
According to a first aspect of the invention, since the sealing member is provided with the sub-lips in addition to the main lips, more portions can be sealed against the air conditioning case in comparison with a conventional sealing member provided with the main lips alone, thereby making it possible to enhance sealing.
Also, when the heat exchanger is inserted into the air conditioning case in a longitudinal direction of the sealing member, since the sub-lips are formed to branch from the surfaces of the plates forming their respective main lips, the stiffness of the main lips can be enhanced to resist a shear force Ps applied when the heat exchanger is rubbed against the air conditioning case during insertion. Hence, unwanted deformation occurring at the end portions of the main lips can be controlled, thereby making it possible to enhance the sealing ability of the sealing member.
Incidentally, the lip extending in a longitudinal direction is linked directly to the lip extending in a lateral direction in the conventional sealing member, and therefore, these lips interfere with each other when they undergo elastic deformation. Such interference causes unwanted deformation in close proximity to the corner meeting portion of the lips, which impairs the sealing ability.
By taking this into account, a second aspect of the invention is configured in such a manner that the sealing member has a corner portion extending to bend at nearly a right angle along a corner portion of the heat exchanger and connecting the main lip extending in a longitudinal direction and the main lip extending in a lateral direction, and that the corner portion is formed as a thin film that is thinner than the main lips.
According to the second aspect, when the main lips undergo elastic deformation when being pressed against the air conditioning case, the corner portion can be readily folded, which makes it possible to control interference between the main lips. Hence, the occurrence of unwanted deformation in close proximity to the corner portion of the main lips can be controlled, thereby making it possible to enhance the sealing ability of the sealing member.
A third aspect of the invention is configured in such a manner that a notch is formed in the sealing member at a boundary portion between the main lip extending in a longitudinal direction and the main lip extending in a lateral direction. According to the third aspect, the main lip extending in the longitudinal direction and the main lip extending in the lateral direction can undergo elastic deformation when being pressed against the air conditioning case without interfering with each other. Consequently, the occurrence of unwanted deformation in close proximity to the corner portion of the main lips can be controlled, thereby making it possible to enhance the sealing ability of the sealing member.
A fourth aspect of the invention is configured in such a manner that more than one sub-lip is provided to each of the main lips. According to the fourth aspect, not only can further portions be sealed onto the air conditioning case, but also the stiffness of the main lips can be further improved against a shear force Ps, thereby making it possible to further enhance the sealing ability of the sealing member.
Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention.